Optimum Serious Mass 5455g

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The ULTIMATE weight gain formula.

Add serious mass with 1,250 quality calories per shake.

Support muscle growth with 50 g of proteins and 250 g of carbs per serving.

Enjoy between meals, post-workout &/or before bed.

ON’s Serious Mass is the ULTIMATE weight gain formula. If you find it difficult to gain weight, Serious Mass will help you develop the physique you've always wanted!


What Does It Do?

Each delicious shake delivers an incredible 1,250 calories, but no added sugar. This includes 50 g of blended protein to support muscle growth and 250 g of carbohydrates. Supports growth of lean muscle mass


When Is The Best Time To Enjoy My Shake?

Simply mix up 2 scoops with milk or water in your ON shaker and enjoy between meals, post-workout and/or before bed.

No surprise that customers voted Serious Mass ‘Weight Gainer of the Year’ at the recent Bodybuilding.com Awards!

Suitable for vegetarians.


Nutritional value in one serving
Energy 1250 kcal
Protein 50 g
Carbohydrates 250 g
Fat 5 g
*% RDA – percent of the recommended daily allowance
Free shipping

Next day delivery (from monday to friday) for orders above 50€

Same day delivery

Same day delivery available in Tallaght, Dublin 24 for orders above 50€

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